<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>演示数据</title>
</head>
<body>
    <select id="nr" name="wan">
        <option value="10">每页显示10条</option>
        <option value="20">每页显示20条</option>
        <option value="50">每页显示50条</option>
        <option value="100">每页显示100条</option>
    </select>
</body>
</html>